Growing energy demand and the necessity for green power generation leads to a constant increase in wind energy exploitation. Driven by the need for higher yields, rotor diameters are constantly increasing over the recent years. Due to the shortage of sites with high wind resources, wind energy moves closer to residential areas for local power supply, where noise emission is one of the main aspects for high acceptance. Reducing noise emission during the design phase or measuring the noise emission on the rotor blade is therefore a primary goal. Furthermore, measuring noise emission enables optimized control loops and opens doors to new opportunities for specifically silent turbines.
At present, no sensor is available for measuring quasi-static and unsteady pressure on surfaces of rotor blades in operation that withstands the harsh conditions. In close cooperation with ENERCON GmbH, fos4X GmbH developed a durable pure glass field-sensor for surface integration in rotor blades of wind turbines.
Herewith, we introduce the passive fiber-optic pressure sensor with diameter of 2x3x10 mm³, real surface membrane, natural frequency above 250 kHz, 40 kPa linear transfer characteristic, overpressure-resistance above 50 times full-scale, and without conductive and corrosive materials. Wind-tunnel validation and field test verification with around 150 sensors on a modern multi-megawatt wind turbine by ENERCON were carried out and will be presented in detail.